Dynamo-electric machine.



A PETENTED JUNE 2, i908.

V. C. APPLE. DYNAMC ELECTRIC MACHINE.

um Uwnll un APPLICATION FILED MAY 11I 1907.

Machines, of `which the uNrrED STATESN PATENT OFFICE.

v VINCENT e. APPLE, or DAYTON, OHIO, AssieNon To DAYTON EL'ao'raIoaLMANUFAOTURING OO., A CORPORATION OF OHIO.

DiNnMo-ELECTRIO MACHINE.

Specification of Letters Patent.

.Patented annee, isos.

Application filed May 11, 1907. Serial No. 371 3,055.

To all whom tt may concern: Be it known that I, VINOENTG, APPLE, acitizen of the United States, residing at Dayton, in the county ofMontgomery and State of Ohio, have invented certain new and usefulImprovements in Dynamo-Electric following is a specification.

My invention relates to improvements in dynamo electric machines, andhas for its general Object to provide a dynamo electric machineinvolving a field pole construction which is -mechanically ,andelectrically ad vantageou's.

I have found that in dynamo construction great advantage may be attained bny providing a pole tube supported by an -making/ magnetic contactwith the pole cores,such tube providing a free, trulycylindrical,'central area, in which the armature may revolve, and being attenuatedto extreme thinn ess between the ole cores. ASuch construction ismechanica ly advantageous in that the single pole tube, which may beldriven in `endwise and make a 'driving fit with the pole cores,operates to hold in place upon the cores all of the iield windings,thereby producing an extremely simple structure, `easy to manufactureand readily assembled, and I have further found that such constructionhas many electrical advantages, Acertain of which are, that it resultsinthe production of a stable field, wherein a commutation point ismaintained. so close to the theoretical neutral .commutation point,rthatWithout change of armature maybe made very small without lfor ythemagnetism'in the dynamo frame, so

that ample residual magnetism is retained to cause the machine 'to-.\buil/d .up its' field quickly, and theslight shortecircuiting effect ofthe attenuated connection ,between the poles tends V'to preventthe'ma'gnetic' lines i from ybending'back'from vthe polar surfacestoward the frarn'e,.while the extremeattenuation atpointsjbetween.adjacentlgpolesipre#` tion, taken in conjunction with theaccompanying drawings, wherein: y

Figure l is a central vertical 'section through a small dynamo embodyingmyinvention F ig. 2 is a cross section on line 27-2 of Fig. 1. l

. Throughout the views like numerals 'of reference refer always to likeparts.

In the drawings I have illustrated my in# vention as applied Lto a smallbi-polar dynamo of a construction which I have prac tically embodied,but it will be understood that I do not intend to limit m T invention tothe particular embodiment s own, further than as specified in theclaims.

In the drawings 5 ,indicates a dynamo frame of suitable construction,illustrated .as

comprising a casting affording a closed 'casing, comprising. a centralring 6, having. iormed-tiereln 1n casting internal inte ra' projections7, constituting the olesoreid C core.I The interior surfaces o thesepoler cores are made truly arcuate, as by proper i previously wound andinsulated detachable y coils.

9 indicates in general the pole tube, which is preferably a soft steeltube, haviriga continuous uninterrupted interior surface, trulycylindrical throughout its entire length, and is generally of athickness suitable for a ole shoe in proportion to the requirements othe machine. At suitable points, as 10, spaced to be positioned midwaybetween contiguous 'pole core surfaces, the tube is attenuatedthroughout its entire length to eXtreme thinness, in a practicalconstruction of a small dynamo approximately one andv Aone "half timesthe size indicated .in the drawings, the pole tubo has been reduced froma thickness of about one eighth of an inch to approximately three onethousandths of an inch.

For effecting this lattenuation I prefer` that the exterior ofthe tubebe -dressed flat, as indicated in thedrawings in Fig. 2, so that theattenuation may bel gradual, as this cient. 'At oneend, nir-theelprefer1 that the. erteriru:l of the tubo Should be dressed away,formation is simpledeasy to make and efhvsomewhat to produce an'exterior taper, as shown at il. In assembling the parts the lield coilsS are placed upon the cores 7, and the pole tube, 9, has its tapered end11 inserted between the` cores 7 and is driven home, so that it projectslongitudinally beyond the pole cores-7 at both ends, and etiectuallysupports in position the field windings S, the arrangement being asindi- 'cated in Fig. 2, such that the portions of eX- treme attenuation10, stand halt way between the poles 7 on opposite sides.

bviously in a machine involving a greater number of goles` anattenuation isprovided in a pole ring midway between the approximatesurfaces oi' each pair oi' adjoining poles.

l2 indicates the armature, of any suitable form, arranged for rotationwithin the cylinder core of the pole tube, such armature being.)referat/)ly constructed to have a very small clearance with respect tosuch interior surface ol the pole tube, and' being otherwise of anysuitable arrangement. The construction and mounting ol? the armature 12,commutator 13 and other apl'iropriateparts of the machine form no partof the present invention and need not be specifically described, as itwill be understood that any suitable construction may be employed andthat shown is illustrative only.

Having thus described my invention, whatl I claim and desire to secureby Letters Patent, of the United States, is: g

l. In a dynamo electric machine, field pole cores, and a continuousconnecting pole tube of paramagnetic material, attenuated between theole cores.

2. In a ynamo electric machine, field pole tores, and a continuousconnecting pole tube of ara-magnetic material, attenuated in thic nessbetween the pole cores, and pre- A riory a truly cylindrical unbrokensurface,

such tube exteriorly interiitting in self-sustaining relation with thepole cores, and being attenuated to extreme thinness between said polecores.

5. In a dynamo electric machine, a field' frame-structure comprising acontinuous iield ring and inwardly projecting pole cores integraltherewith, said pole cores being arcuate at their inner surfaces, ieldcoils surroundingr the cores, and a ole tube of paramagneticrriaterial,l interior y cylindrica, interiitting snugly m said arcuatesullaces of the pole cores, i or retention by said cores and to su portthe iield windings upon said cores, t 1c pole tube being attenuated toextreme thinness between the pole cores. d

6. In a dynamo electric machine, pole cores, and a connecting indeendent pole tube of paramagnetic materia of generally cylindrical form,attenuated to extreme thinness on straight lines parallel to the tubeaxis, between adjacent ole cores.

In testimony whereotPI. hereunto set my hand in thfpresence of twowitnesses.

"VINCENT- G. APPLE.

In the presence of- E. M. GIQIER, H. E. SNYDER;

